Medical student Martha Jones is trying to solve a family squabble involving her divorced parents, Clive and Francine, and her siblings, Tish and Leo, when she encounters the Doctor at the hospital where she works. The Doctor is masquerading as a patient, having observed strange phenomena nearby. Too late, he realises that it's the work of the Judoon, ruthless intergalactic policemen-for-hire who hijack the hospital to the Moon. The Judoon are tracking a blood-sucking alien fugitive called a Plasmavore... and the Plasmavore will stop at nothing to avoid capture.

Having already regenerated the Doctor, executive producer Russell T Davies confronted another Doctor Who tradition as he began to plan for Season Twenty-Nine: the introduction of a new companion. Rose Tyler, as played by Billie Piper, had been an extremely popular character; Davies was keenly aware that her successor would have to be equally likeable and versatile, but without being a mere carbon copy. With this in mind, early ideas such as a sixteen-year-old schoolgirl were jettisoned. Another possibility was a maid from the Victorian era or the early twentieth century, inspired by the interaction between the Doctor and Reinette in 2006's The Girl In The Fireplace, but this notion was discouraged by Jane Tranter, the BBC's Controller of Drama Commissioning.

Finally, Davies devised medical student Martha Jones who, at age twenty-three, would represent a slightly older, more sophisticated woman than Rose, relying more on book smarts than instinct. As with Rose in 2005, Davies was keen that Martha's first story, the Season Twenty-Nine premiere, should focus firmly on the new companion. It would also introduce Martha's family -- divorced parents Clive and Francine, older sister Tish, and younger brother Leo -- in much the same way that Jackie Tyler and Mickey Smith had debuted in Rose. However, Davies had decided that Martha's supporting coterie would have a diminished presence compared to Rose's.

Freema Agyeman had unsuccessfully auditioned for the role of Sally in The Christmas Invasion

An early candidate to portray Martha was Freema Agyeman, who had unsuccessfully auditioned for the role of Sally in 2005's The Christmas Invasion. Despite the decision against casting Agyeman in that episode, she had nonetheless impressed the production team, and she was eventually chosen to play the ill-fated Adeola in the 2006 finale, Army Of Ghosts / Doomsday. Unbeknownst to Agyeman, this was privately considered a preliminary audition for Martha; producer Phil Collinson, in particular, kept a close eye on her performance.

Agyeman was then invited to an audition on January 17th, 2006 for what she believed to be the role of Gwen Cooper in the forthcoming spin-off series Torchwood. In fact, she was reading for Martha Jones; a second audition followed on February 3rd, after a brief delay while Agyeman recovered from an illness. Now nervously aware that she was in the running for a regular role in Doctor Who, Agyeman had a screen test with David Tennant on February 15th. Two days later, she learned that she was the successful applicant. Working at a Blockbuster Video while she was between acting jobs, Agyeman took the opportunity to learn more about the history of Doctor Who. On June 16th, the Sun leaked her “front-runner” status to play the new companion. Finally, the BBC confirmed on July 5th that Agyeman was joining the cast of Doctor Who.

For Season Twenty-Nine, Davies was determined to discourage leaks by waiting to assign episode titles until it was absolutely necessary. He believed that too much information about Season Twenty-Eight had been prematurely divulged, and that this had been to the show's detriment. All the same, he considered following in the footsteps of Rose by naming Agyeman's debut “Martha”. Since the new character needed to be at the centre of the action, Davies felt that her place of work was an ideal setting for the narrative, with the Doctor originally brought in on a stretcher after having been knocked unconscious by the Plasmavore. To keep the focus on Martha, Davies dropped a key plot strand in which the Doctor and the Plasmavore each strove to reach the hospital basement, where the TARDIS was hidden.

When he was initially meeting with the BBC about reviving Doctor Who, one of the ideas Davies had proposed was a set piece in which the Doctor and his companion escaped danger using a window cleaner's cradle. For a long time, this sequence was intended to feature in “Martha”, with the Doctor and Martha evading the pursuing Judoon by descending the exterior of the hospital. It was eventually excised due to its length; it would eventually be incorporated into the 2008 premiere episode, Partners In Crime. Meanwhile, with the action of “Martha” taking place in a hospital, Davies chose to name its administrator after Mr Stoker, a character in the family programme Children's Ward. However, the presence of a blood-sucking monster led the design team to assume that Davies was referencing Bram Stoker, author of the 1897 horror classic Dracula. As a result, the character's office door bore the legend “B Stoker”.

Trevor Laird (Clive Jones) had appeared as Frax in 1986's The Trial Of A Time Lord

With The Runaway Bride having comprised the first production block for the new set of episodes, Block Two consisted of “Martha” and The Shakespeare Code, which was to follow it in the broadcast order. The director assigned to these stories was Charles Palmer, who had worked with Doctor Who producer Phil Collinson on Linda Green. Although this was his first assignment on the show, his father, Geoffrey Palmer, had played Masters in 1970's The Silurians and the Administrator in 1972's The Mutants. Palmer also knew Gugu Mbatha-Raw from his work on Vital Signs; she was now cast as Tish. The other Jones sibling, Leo, would be played by actor, presenter and disc jockey Reggie Yates. The role of Francine went to Adjoa Andoh, who had been Sister Jatt in the previous year's New Earth. Finally, Trevor Laird would portray Clive, returning to Doctor Who after appearing as Frax in the second segment of 1986's The Trial Of A Time Lord.

Filming for “Martha” got under way on August 8th. The principal stand-in for Royal Hope Hospital was the School of Sciences at the University of Glamorgan in Pontypridd, where Agyeman recorded her first scene as Martha, rounding on patients with Stoker. After a second day at the University on the 9th, August 10th saw Martha walking to work and encountering the Doctor for the first time at Quay Street in Cardiff. The rest of the 10th and the 11th were then spent at Doctor Who's regular studio facilities at Upper Boat for sequences in the TARDIS and on the hospital verandah. Dialogue had been added to the episode to establish that Martha and Adeola were cousins, explaining their physical similarity. The Doctor mouthing along to Martha's comment about the TARDIS being “bigger on the inside” was an ad-lib suggested by Tennant.

After the weekend, August 14th took cast and crew to the Usk Valley Business Park in Pontypool for various hospital corridor sequences. Four more days at the University of Glamorgan followed, spanning the 15th to the 18th. Next, August 19th and 21st were scheduled for Singleton Hospital in Swansea. This venue provided the exterior of Royal Hope Hospital as well as further interiors, including the foyer, the stairwell, and additional corridors. Unfortunately, the time-consuming shots which turned six artistes into dozens of Judoon forced Palmer's team to remain in Swansea on the 22nd, postponing a final visit to the University. On August 23rd, the kitchens at Upper Boat Studios filled in for those of Royal Hope Hospital; this was amongst the material originally intended for the previous day.

The other set of shots deferred from August 22nd were those in the X-ray room, and they were finally completed at the University of Glamorgan on the 25th. Because Palmer was busy shooting scenes for The Shakespeare Code at this point, James Strong -- who had directed The Impossible Planet / The Satan Pit the previous season -- was drafted to oversee the day's work. Green screen shots and various inserts were recorded at Upper Boat on September 12th. The next day, the Doctor and Martha's alleyway conversation outside the TARDIS was filmed on Market Street in Pontypridd. As originally written, Tish also appeared in this scene, dashing through the background in pursuit of Annalise. However, the action was simplified so that Mbatha-Raw would not have to be summoned for such an incidental role.

By mid-September, the episode had received its final title of Smith And Jones. This played on the ubiquity in the English-speaking world of both the Doctor's assumed surname and Martha's actual family name, while also recalling the Western series Alias Smith And Jones and the sketch show Alas Smith And Jones. Virtually all of the material involving Martha's family was recorded during Block Three, when Andoh, Mbatha-Raw and Yates were also required for The Lazarus Experiment. Most of these sequences were shot on October 2nd in Pontypridd -- largely on Tyfica Crescent, although the argument at Leo's party saw cameras again rolling on Market Street as well as nearby Taff Street. The exception was Tish approaching Royal Hope Hospital, which was performed on October 13th along Queen Street and The Friary in Cardiff.

The original effect for the Judoon weapons -- in which the victim's skin boiled away -- was too frightening

Davies had now come to feel that the transition to Leo's party at the end of the episode was too abrupt. As such, he wrote an additional scene in Martha's living room, which was recorded at Upper Boat Studios on October 19th. This material also provided the opportunity to insert a reference to Mr Saxon, the character who would loom large in the story arc spanning Season Twenty-Nine. Extra dialogue in the hospital corridors, with Martha asking the Doctor if he has back-up, was filmed on November 7th at the former Nippon Electric Gas site in Cardiff. A remount of Martha resuscitating the Doctor was completed at the same time. However, a continuity error had now crept in, with the Doctor using his sonic screwdriver to open the X-ray room door despite the fact that it had already been destroyed at that point in the narrative. After the mistake was noted by brand executive Edward Russell, Palmer corrected it with additional shots at Upper Boat Studios on January 17th, 2007. Meanwhile, it had been decided that the original visual effect for the Judoon weapons -- in which the victim's skin would be seen to boil away -- was too frightening, and so this was altered.

The first two seasons of the revived Doctor Who had each debuted on Easter Saturday. But while the March premiere in 2005 had not been a cause for concern, the April start in 2006 had pushed the latter episodes of Season Twenty-Eight into July. Given the drop in viewing figures which typically accompanied hot summer weather, and with Easter Saturday falling on April 7th in 2007, it was agreed to abandon this approach for Season Twenty-Nine. Instead, Smith And Jones was earmarked for a March 17th airdate. However, Doctor Who was then postponed by a week to avoid the season finale of ITV1's successful reality competition Dancing On Ice, and then -- at a very late stage -- by another week to avoid Sky Sports' broadcast of the European Championship qualifier pitting England against Israel.

As a result, Smith And Jones was finally broadcast on March 31st. Doctor Who was scheduled in the same 7.00pm time slot which had been its home for most of Season Twenty-Eight, and which had been without a regular occupant so far in 2007. It was preceded by The National Lottery People's Quiz, and led into the debut of the Andrew Lloyd Webber reality series Any Dream Will Do. Meanwhile, on March 22nd, Davies at last confirmed what the production team had known for some time: that Doctor Who would be returning for its landmark thirtieth season in 2008...

• Doctor Who Magazine Special Edition #17, 22nd November 2007, “Episode 1: Smith And Jones” by Andrew Pixley, Panini Publishing Ltd.
• Doctor Who: The Complete History #54, 2017, “Story 179: Smith And Jones”, edited by John Ainsworth, Hachette Partworks Ltd.